1. Field of the Invention
The present invention relates to ultrasonic diagnostic apparatus. More specifically, the present invention is directed to a diagnostic probe having an ultrasonic sector scanner.
2. Description of the Prior Art
Ultrasonic analysis is a commonly used technique for producing a tomogram for viewing internal anatomy. This technique has particular utility in so-called real time imaging whereby the images are produced sequentially at a rate sufficiently high to enable dynamic visualiztion of the motion of internal organs. The irradiation of the human tissue by the ultrasonic wave produces output signals from the scanning device by differing attenuation of the reflected ultrasonic wave between differences in structure of the internal organs. Thus, the tomogram is obtained by utilizing the echo of the ultrasonic wave. In utilizing such an ultrasonic diagnostic apparatus, the proximity method uses a technique wherein an ultrasonic probe is placed in contact with the surface of the body under examination while isolating the scanning transducer from the point of contact. Such a technique enables the ultrasonic beam to be scanned through the space between two adjacent ribs or any other area which would allow transmission of the ultrasonic beam. In producing such a diagnostic device, the apparatus must be capable of being handheld in operation particularly where the proximity method is used in the real time cardiac imaging. In order to achieve the direct contact between the probe and the human anatomy, the ultrasonic probe is immersed in a medium capable of transmitting the ultrasonic beam and allowing a scanning motion of the transducer while the surface of the probe which seals the transmitting medium within the probe must also be transparent to the ultrasonic beam and match the acoustic properties of human tissue.